Smart cards, also known as chip cards or integrated circuit cards, are typically pocket-sized cards with embedded integrated circuits, capable of communicating with a reader and processing communicated data. Common applications for smart cards include, for example, their use as electronic wallets, credit or ATM cards, fuel cards, high-security identification and access-control cards, public transport and public phone payment cards, identification cards, drivers' licenses, patient cards, and so on.
Commonly used smart cards may have a contact interface, or a contactless interface, or both. Contact smart cards have a contact area, comprising several metallic contact pads, typically totaling approximately one square centimeter on the face of the card. When inserted into a card reader, the contact plate of the smart card aligns with the electronic contacts inside the reader, and data is transmitted over the electrical connection. One standard for contact smart card is ISO/WEC 7816, the contents of which are incorporated herein by reference.
As their name suggests, contactless smart cards may transfer data between the card and the card reader without requiring electrical contact. A contactless transaction may occur when the cardholder presents the contactless smart card within a required proximity from the card reader. The data may be conveyed across this distance via radio frequency (RF) electromagnetic field signals. One standard for contactless smart card communications is ISO/WEC 14443, the contents of which are incorporated herein by reference, which defines two types of contactless cards, “A” and “B”, and allows for communications at distances up to 10 cm. An alternative standard for contactless smart cards is ISO 15693, the contents of which are incorporated herein by reference, which allows communications at distances up to 50 cm. It will be recognized that despite the name smart card, because contactless environments eliminate the need to physically insert the card into a reader, contactless smart cards need not to be in card form, but may take the form of a key fob, a wristwatch, a bracelet, a sticker, a ring, etc.
Some smart cards can support both contact and contactless modes, and are referred to as dual mode or contact/contactless smart cards. In such dual mode cards, the communication protocol may be different for the contact and the contactless modes of operation. A dual mode card may typically determine whether the card is used in contact or contactless mode by sensing the source of the power supply to the chip. Contact mode may be enacted if the operating voltage is supplied via C1 (VCC pad of the contact pads) and contactless mode may be enacted if operating voltage is supplied via the RF field, typically when an operating voltage is not sensed via C1. “Mixed” mode is a special combination mode that may be further supported by some dual mode smart cards. Mixed mode may define simultaneous operation in both contact and contactless modes. In such case, the smart card may simultaneously be accessed by contact and contactless readers. Hence, power, bidirectional data communication, reset and clock signals, are available from both sources. In such cases, the card is typically required to handle communication with both readers, while selecting (typically under software control) which operating voltage, reset and clock signals to use (contact or contactless).
Generally, smart cards support one application, e.g., a particular credit card. However, modern consumers may have many such applications, e.g., a plurality of cash and credit cards, fuel cards, high-security identification and access-control cards, public transport and public phone payment cards, citizen identification cards, drivers' licenses, patient card, and so on. If each card supports an application, a consumer may be required to carry a large number of smart cards, which may be cumbersome.